The invention relates to toothbrushing technique monitoring.
The effectiveness of toothbrushing in removing plaque from tooth surfaces is affected by the user""s brushing motion, brushing duration, and the force applied by the user during brushing. These parameters have been integrated by dental professionals to form a xe2x80x9crecommended brushing techniquexe2x80x9d which is taught to dental patients during visits to the dentist. However, once the patient leaves the dentist""s office, this technique is often forgotten, and poor brushing technique is used instead. Moreover, if the dentist asks the patient to demonstrate the patient""s brushing technique, such a demonstration is often not representative of the patient""s usual technique.
Various toothbrushes have been proposed which measure one or more of the three parameters discussed above and provide a signal (e.g., a sound or light) when these parameters are not within predetermined optimal ranges. Other toothbrush systems monitor one or more of these parameters and provide a graph that plots the raw data obtained during monitoring.
The invention provides a toothbrush user and/or the user""s dentist with an accurate evaluation of the user""s brushing technique during a brushing session. The invention acquires a time sequence of data regarding the user""s brushing motion, force and duration during brushing, stores the data, and then analyzes it. A user interface allows the toothbrush user and/or the user""s dentist to view a simulation of a brushing session. Data from multiple brushing sessions may be stored so that a history of the patient""s brushing technique and regimen can be compiled and studied.
In one aspect, the invention features a method including, while a toothbrush user is brushing his teeth, acquiring data indicative of motion of the toothbrush along its longitudinal axis, and, providing information about the data for display.
Preferred implementations of the method include one or more of the following features. The method further includes acquiring data indicative of motion of the toothbrush in at least two degrees of freedom, more preferably at least 4 degrees of freedom and most preferably six degrees of freedom. The method further includes acquiring data indicative of pressure applied along the shafts of the bristles. The data indicative of motion is acquired independently of the pressure data. The data indicative of motion is acquired from a location in the vicinity of the bristles, e.g., from an elongated member having a longitudinal axis that is disposed at an angle of 0 to 45 degrees with respect to the shafts of at least some of said bristles. The data is acquired by measuring strain as the elongated member is deflected during brushing. The method further includes analyzing the data to determine the brushing motion of each brushstroke. The information is displayed to a dentist and/or to the user of the toothbrush, or the information is used in clinical or market research. The information includes detail about brushing motions used during brushing, relates to brush wear, and/or relates to brushing pressure. The information is used to control movement of a graphical element, representative of a toothbrush, in accordance with the data. The information includes detail about how much brushing occurred on the left, right and front teeth.
In another aspect, the invention features a system for monitoring a toothbrushing technique of a user, including (a) a toothbrush constructed to acquire a time sequence of data, indicative of a changing two-dimensional position of bristles of the toothbrush in a plane that is generally perpendicular to shafts of the bristles of the toothbrush, and (b) a user interface constructed to display information concerning the brushing motions of the user.
Preferred implementations of this aspect of the invention may include one or more of the following features. The system further includes a data storage device associated with the toothbrush and constructed to store the data acquired by the toothbrush. The user interface is constructed to provide an evaluation of the user""s brushing technique based on said data. The toothbrush includes the user interface, or the user interface is provided on a toothbrush holder. The user interface includes a display for indicating a rating. The toothbrush includes a modem, e.g., a wireless modem, for transmitting the data to a remote computer. The user interface includes a display including a first graphical element, representative of a toothbrush, that moves in accordance with the data. The display further includes a second graphical element, representative of a set of teeth, that remains static relative to the first graphical element. The first graphical element appears to move in any of six degrees of freedom. The toothbrush includes a sensor and a microprocessor.
In another aspect, the invention features a toothbrush including a handle, a neck, and a brush region extending from the neck, the brush region including brushing elements extending from a base, and a motion sensor disposed in the brush region.
Preferred implementations include one or more of the following features. The brush region further includes a back portion, the sensor is mounted on the back portion, and the base is removably mounted on a portion of the sensor extending from the back portion. The brushing elements and the base together comprise a removable modular unit. The modular unit is replaceable. The sensor is permanently mounted on the toothbrush, and the modular unit removably engages a portion of the sensor. Alternatively, the sensor includes an elongated member that extends between the brushing elements, e.g., a portion of the elongated member extends through an aperture in the base and into the brushing elements. The brushing elements comprise bristles and the longitudinal axis of the elongated member extends at an angle of from about 0 to 45 degrees with respect to the long axes of at least some of the bristles. The sensor includes a bristle-like element. The toothbrush further includes a rotation sensor, e.g., a gyroscope, constructed to measure rotation of the toothbrush. The motion sensor is constructed to measure a bending moment of the elongated member when force is applied by the user to the teeth during brushing. The motion sensor measures bending moments in multiple directions. The toothbrush further includes a data storage device for storing data that is sensed by the sensor. The toothbrush further includes a modem, e.g., a wireless modem, for transmitting data that is sensed by the sensor to a remote computer. The toothbrush further includes a data evaluation device constructed to analyze the data. The toothbrush further includes a display for displaying information regarding a brushing session. The toothbrush further includes a microprocessor connected to the sensor.
In another aspect, the invention features a method including displaying a first graphical element representative of a toothbrush; and causing the first graphical element to move in accordance with data that represents actual motion of a toothbrush held by a user.
In preferred implementations, the display further includes a second graphical element, representative of a set of teeth, that remains static and is positioned relative to the first graphical element so that the first element appears to be moving over the second element.
In a further aspect, the invention features a method for evaluating a toothbrush user""s toothbrushing technique including (a) while a toothbrush user is brushing his teeth, acquiring data associated with the user""s toothbrushing; (b) storing data acquired during the toothbrushing step; (c) analyzing the data to obtain an evaluation of the movement of the brush and, independently, the pressure exerted on the teeth; and (d) providing information about the evaluation for display.
In another aspect, the invention features a toothbrush including a body, and a sensor constructed to generate a time sequence of data associated with orientation of the toothbrush in enough degrees of freedom to enable a determination of the motion of the toothbrush independently of the force applied by a user to teeth during brushing.
In yet another aspect, the invention features an apparatus including (a) an input configured to receive a time sequence of data associated with orientation of a toothbrush during brushing, and (b) an analytical device that determines the contour of the motion of the toothbrush based on said data.
In a further aspect, the invention features a machine-based user interface that includes a display of a toothbrush in a 3D world, and a device that controls apparent motion of the toothbrush in the 3D world in accordance with data about orientation of a real toothbrush derived during toothbrushing.
In another aspect, the invention features a toothbrush including (a) a brush portion for brushing the teeth; (b) a brushing evaluation device; and (c) a display, for displaying information generated by the brushing evaluation device.
In preferred implementations, the information includes detail about brushing motions used during brushing, brushing pressure and brush wear. The display may also indicate when the brush portion should be replaced.
In a further aspect, the invention features a toothbrush that includes a replaceable brush portion, a data acquisition device constructed to acquire and store data pertaining to brushing pressure, duration, and number of brushstrokes, and an indicator constructed to evaluate the data and indicate to a user of the toothbrush when the brush portion should be replaced.
The invention also features other methods and devices for monitoring toothbrushing technique.
Other features and advantages will be apparent from the following description and from the claims.